HTML is not converted to wiki syntax when form enctype=multipart/form-data

Request parameters are not populated when a form is submitted with enctype=multipart/form-data (SRV4.1.1). As a consequence the conversion filter fails to detect the form fields that need to be converted. Note that com.xpn.xwiki.web.Utils.handleMultipart(HttpServletRequest, XWikiContext) wraps the request and populates the parameters but it is called in com.xpn.xwiki.web.XWikiAction.execute(XWikiContext) so after the conversion filter.